Seismo-acoustic detection and tracking of small aircrafts

Abstract

The Army Research Laboratory is undertaking an investigation to combine acoustic and seismic vector sensors, in conjunction with traditional acoustic arrays which use omnidirectional microphones, to detect and track small airplanes. The focus of this study is to improve the fidelity of the track with a sparse network and explore its applicability in both urban and rural settings. Towards this end, we carry out a field test where multiple aircrafts with known flightpaths are acoustically and seismically monitored over a period of several days. Using a detection algorithm that leverages both the blade frequency of the propellers and the Doppler associated with near-source propagation, we demonstrate that both acoustic and seismic data have the ability to detect and track the aircrafts. Both acoustic and seismic vector sensors have the ability to estimate both the arrival time and the azimuth to the source which lead to smaller sensor footprint. By combining multimodal sensing with novel target tracking techniques, we can reduce the impact of clutter while maintaining a robustness of our detection and tracking algorithms. A comparison of the acoustic and seismic vector sensors in tracking small aircrafts will be discussed.